Multicast Path Traces

This application is a continuation U.S. patent application Ser. No. 18/088,239, filed on Dec. 23, 2022, entitled MULTICAST PATH TRACES, by Mankamana Prasad Mishra et al., the contents of which are incorporated herein by reference.

The present disclosure relates generally to computer systems, and, more particularly, to multicast path traces.

The Internet and the World Wide Web have enabled the proliferation of web services available for virtually all types of businesses. Due to the accompanying complexity of the infrastructure supporting the web services, it is becoming increasingly difficult to maintain the highest level of service performance and user experience to keep up with the increase in web services. For example, it can be challenging to piece together monitoring and logging data across disparate systems, tools, and layers in a network architecture. Moreover, even when data can be obtained, it is difficult to directly connect the chain of events and cause and effect.

For example, IP multicast is a popular method of one-to-many data distribution. Multicast data distribution involves transmitting a packet from a source to an arbitrary number of receivers by replicating the packet within the network at fan-out points along a multicast distribution tree rooted at the traffic's source. Accordingly, a packet may be received by multiple receivers across multiple branches of the multicast tree.

Multicast trees can be difficult to troubleshoot. For instance, there is no efficient and/or deterministic mechanism to identify the topology of a distribution tree in a node-agnostic manner. Instead, current techniques for route tracing in a multicast tree are directionally limited (e.g., upstream tracing only) and/or limited to receiver-to-source tracing beginning at a last hop router (LHR). As a result, the current path tracing techniques for multicast trees are not globally applicable across all nodes of the multicast tree and, therefore, are unable to provide visualization of the entire multicast tree from any part of the network

According to one or more embodiments of the disclosure, a device may receive a multicast path trace request for a multicast tree, wherein the device is a mid-node in the multicast tree. The device may perform, based on the device being a mid-node in the multicast tree, an upstream trace of network topology of the multicast tree from the device to a head-node of the multicast tree and a downstream trace of network topology of the multicast tree from the device to at least one tail-node. The device may generate an end-to-end visible topology of the multicast tree based on the upstream trace and the downstream trace. The device may provide the end-to-end visible topology of the multicast tree to an observability manager.

Other embodiments are described below, and this overview is not meant to limit the scope of the present disclosure.

A computer network is a geographically distributed collection of nodes interconnected by communication links and segments for transporting data between end nodes, such as personal computers and workstations, or other devices, such as sensors, etc. Many types of networks are available, ranging from local area networks (LANs) to wide area networks (WANs). LANs typically connect the nodes over dedicated private communications links located in the same general physical location, such as a building or campus. WANs, on the other hand, typically connect geographically dispersed nodes over long-distance communications links, such as common carrier telephone lines, optical lightpaths, synchronous optical networks (SONET), synchronous digital hierarchy (SDH) links, and others. The Internet is an example of a WAN that connects disparate networks throughout the world, providing global communication between nodes on various networks. Other types of networks, such as field area networks (FANs), neighborhood area networks (NANs), personal area networks (PANs), enterprise networks, etc. may also make up the components of any given computer network. In addition, a Mobile Ad-Hoc Network (MANET) is a kind of wireless ad-hoc network, which is generally considered a self-configuring network of mobile routers (and associated hosts) connected by wireless links, the union of which forms an arbitrary topology.

is a schematic block diagram of an example simplified computing systemillustratively comprising any number of client devices(e.g., a first through nth client device), one or more servers, and one or more databases, where the devices may be in communication with one another via any number of networks. The one or more networksmay include, as would be appreciated, any number of specialized networking devices such as routers, switches, access points, etc., interconnected via wired and/or wireless connections. For example, devices-and/or the intermediary devices in network(s)may communicate wirelessly via links based on WiFi, cellular, infrared, radio, near-field communication, satellite, or the like. Other such connections may use hardwired links, e.g., Ethernet, fiber optic, etc. The nodes/devices typically communicate over the network by exchanging discrete frames or packets of data (packets) according to predefined protocols, such as the Transmission Control Protocol/Internet Protocol (TCP/IP) other suitable data structures, protocols, and/or signals. In this context, a protocol consists of a set of rules defining how the nodes interact with each other.

Client devicesmay include any number of user devices or end point devices configured to interface with the techniques herein. For example, client devicesmay include, but are not limited to, desktop computers, laptop computers, tablet devices, smart phones, wearable devices (e.g., heads up devices, smart watches, etc.), set-top devices, smart televisions, Internet of Things (IoT) devices, autonomous devices, or any other form of computing device capable of participating with other devices via network(s).

Notably, in some embodiments, serversand/or databases, including any number of other suitable devices (e.g., firewalls, gateways, and so on) may be part of a cloud-based service. In such cases, the servers and/or databasesmay represent the cloud-based device(s) that provide certain services described herein, and may be distributed, localized (e.g., on the premise of an enterprise, or “on prem”), or any combination of suitable configurations, as will be understood in the art.

Those skilled in the art will also understand that any number of nodes, devices, links, etc. may be used in computing system, and that the view shown herein is for simplicity. Also, those skilled in the art will further understand that while the network is shown in a certain orientation, the systemis merely an example illustration that is not meant to limit the disclosure.

Notably, web services can be used to provide communications between electronic and/or computing devices over a network, such as the Internet. A web site is an example of a type of web service. A web site is typically a set of related web pages that can be served from a web domain. A web site can be hosted on a web server. A publicly accessible web site can generally be accessed via a network, such as the Internet. The publicly accessible collection of web sites is generally referred to as the World Wide Web (WWW).

Also, cloud computing generally refers to the use of computing resources (e.g., hardware and software) that are delivered as a service over a network (e.g., typically, the Internet). Cloud computing includes using remote services to provide a user's data, software, and computation.

Moreover, distributed applications can generally be delivered using cloud computing techniques. For example, distributed applications can be provided using a cloud computing model, in which users are provided access to application software and databases over a network. The cloud providers generally manage the infrastructure and platforms (e.g., servers/appliances) on which the applications are executed. Various types of distributed applications can be provided as a cloud service or as a Software as a Service (SaaS) over a network, such as the Internet.

is a schematic block diagram of an example node/devicethat may be used with one or more embodiments described herein, e.g., as any of the devices-shown inabove. Devicemay comprise one or more network interfaces(e.g., wired, wireless, etc.), at least one processor, and a memoryinterconnected by a system bus, as well as a power supply(e.g., battery, plug-in, etc.).

The network interface(s)contain the mechanical, electrical, and signaling circuitry for communicating data over links coupled to the network(s). The network interfaces may be configured to transmit and/or receive data using a variety of different communication protocols. Note, further, that devicemay have multiple types of network connections via interfaces, e.g., wireless and wired/physical connections, and that the view herein is merely for illustration.

Depending on the type of device, other interfaces, such as input/output (I/O) interfaces, user interfaces (UIs), and so on, may also be present on the device. Input devices, in particular, may include an alpha-numeric keypad (e.g., a keyboard) for inputting alpha-numeric and other information, a pointing device (e.g., a mouse, a trackball, stylus, or cursor direction keys), a touchscreen, a microphone, a camera, and so on. Additionally, output devices may include speakers, printers, particular network interfaces, monitors, etc.

The memorycomprises a plurality of storage locations that are addressable by the processorand the network interfacesfor storing software programs and data structures associated with the embodiments described herein. The processormay comprise hardware elements or hardware logic adapted to execute the software programs and manipulate the data structures. An operating system, portions of which are typically resident in memoryand executed by the processor, functionally organizes the device by, among other things, invoking operations in support of software processes and/or services executing on the device. These software processes and/or services may comprise a one or more functional processes, and on certain devices, an illustrative “path tracing” process, as described herein. Notably, functional processes, when executed by processor(s), cause each particular deviceto perform the various functions corresponding to the particular device's purpose and general configuration. For example, a router would be configured to operate as a router, a server would be configured to operate as a server, an access point (or gateway) would be configured to operate as an access point (or gateway), a client device would be configured to operate as a client device, and so on.

It will be apparent to those skilled in the art that other processor and memory types, including various computer-readable media, may be used to store and execute program instructions pertaining to the techniques described herein. Also, while the description illustrates various processes, it is expressly contemplated that various processes may be embodied as modules configured to operate in accordance with the techniques herein (e.g., according to the functionality of a similar process). Further, while the processes have been shown separately, those skilled in the art will appreciate that processes may be routines or modules within other processes.

As noted above, distributed applications can generally be delivered using cloud computing techniques. For example, distributed applications can be provided using a cloud computing model, in which users are provided access to application software and databases over a network. The cloud providers generally manage the infrastructure and platforms (e.g., servers/appliances) on which the applications are executed. Various types of distributed applications can be provided as a cloud service or as a software as a service (SaaS) over a network, such as the Internet. As an example, a distributed application can be implemented as a SaaS-based web service available via a web site that can be accessed via the Internet. As another example, a distributed application can be implemented using a cloud provider to deliver a cloud-based service.

Users typically access cloud-based/web-based services (e.g., distributed applications accessible via the Internet) through a web browser, a light-weight desktop, and/or a mobile application (e.g., mobile app) while the enterprise software and user's data are typically stored on servers at a remote location. For example, using cloud-based/web-based services can allow enterprises to get their applications up and running faster, with improved manageability and less maintenance, and can enable enterprise IT to more rapidly adjust resources to meet fluctuating and unpredictable business demand. Thus, using cloud-based/web-based services can allow a business to reduce Information Technology (IT) operational costs by outsourcing hardware and software maintenance and support to the cloud provider.

However, a significant drawback of cloud-based/web-based services (e.g., distributed applications and SaaS-based solutions available as web services via web sites and/or using other cloud-based implementations of distributed applications) is that troubleshooting performance problems can be very challenging and time consuming. For example, determining whether performance problems are the result of the cloud-based/web-based service provider, the customer's own internal IT network (e.g., the customer's enterprise IT network), a user's client device, and/or intermediate network providers between the user's client device/internal IT network and the cloud-based/web-based service provider of a distributed application and/or web site (e.g., in the Internet) can present significant technical challenges for detection of such networking related performance problems and determining the locations and/or root causes of such networking related performance problems. Additionally, determining whether performance problems are caused by the network or an application itself, or portions of an application, or particular services associated with an application, and so on, further complicate the troubleshooting efforts.

Certain aspects of one or more embodiments herein may thus be based on (or otherwise relate to or utilize) an observability intelligence platform for network and/or application performance management. For instance, solutions are available that allow customers to monitor networks and applications, whether the customers control such networks and applications, or merely use them, where visibility into such resources may generally be based on a suite of “agents” or pieces of software that are installed in different locations in different networks (e.g., around the world).

Specifically, as discussed with respect to illustrativebelow, performance within any networking environment may be monitored, specifically by monitoring applications and entities (e.g., transactions, tiers, nodes, and machines) in the networking environment using agents installed at individual machines at the entities. As an example, applications may be configured to run on one or more machines (e.g., a customer will typically run one or more nodes on a machine, where an application consists of one or more tiers, and a tier consists of one or more nodes). The agents collect data associated with the applications of interest and associated nodes and machines where the applications are being operated. Examples of the collected data may include performance data (e.g., metrics, metadata, etc.) and topology data (e.g., indicating relationship information), among other configured information. The agent-collected data may then be provided to one or more servers or controllers to analyze the data.

Examples of different agents (in terms of location) may comprise cloud agents (e.g., deployed and maintained by the observability intelligence platform provider), enterprise agents (e.g., installed and operated in a customer's network), and endpoint agents, which may be a different version of the previous agents that is installed on actual users' (e.g., employees') devices (e.g., on their web browsers or otherwise). Other agents may specifically be based on categorical configurations of different agent operations, such as language agents (e.g., Java agents, .Net agents, PHP agents, and others), machine agents (e.g., infrastructure agents residing on the host and collecting information regarding the machine which implements the host such as processor usage, memory usage, and other hardware information), and network agents (e.g., to capture network information, such as data collected from a socket, etc.).

Each of the agents may then instrument (e.g., passively monitor activities) and/or run tests (e.g., actively create events to monitor) from their respective devices, allowing a customer to customize from a suite of tests against different networks and applications or any resource that they're interested in having visibility into, whether it's visibility into that end point resource or anything in between, e.g., how a device is specifically connected through a network to an end resource (e.g., full visibility at various layers), how a website is loading, how an application is performing, how a particular business transaction (or a particular type of business transaction) is being effected, and so on, whether for individual devices, a category of devices (e.g., type, location, capabilities, etc.), or any other suitable embodiment of categorical classification.

is a block diagram of an example observability intelligence platformthat can implement one or more aspects of the techniques herein. The observability intelligence platform is a system that monitors and collects metrics of performance data for a network and/or application environment being monitored. At the simplest structure, the observability intelligence platform includes one or more agentsand one or more servers/controllers. Agents may be installed on network browsers, devices, servers, etc., and may be executed to monitor the associated device and/or application, the operating system of a client, and any other application, API, or another component of the associated device and/or application, and to communicate with (e.g., report data and/or metrics to) the controller(s)as directed. Note that whileshows four agents (e.g., Agent 1 through Agent 4) communicatively linked to a single controller, the total number of agents and controllers can vary based on a number of factors including the number of networks and/or applications monitored, how distributed the network and/or application environment is, the level of monitoring desired, the type of monitoring desired, the level of user experience desired, and so on.

For example, instrumenting an application with agents may allow a controller to monitor performance of the application to determine such things as device metrics (e.g., type, configuration, resource utilization, etc.), network browser navigation timing metrics, browser cookies, application calls and associated pathways and delays, other aspects of code execution, etc. Moreover, if a customer uses agents to run tests, probe packets may be configured to be sent from agents to travel through the Internet, go through many different networks, and so on, such that the monitoring solution gathers all of the associated data (e.g., from returned packets, responses, and so on, or, particularly, a lack thereof). Illustratively, different “active” tests may comprise HTTP tests (e.g., using curl to connect to a server and load the main document served at the target), Page Load tests (e.g., using a browser to load a full page—i.e., the main document along with all other components that are included in the page), or Transaction tests (e.g., same as a Page Load, but also performing multiple tasks/steps within the page—e.g., load a shopping website, log in, search for an item, add it to the shopping cart, etc.).

The controlleris the central processing and administration server for the observability intelligence platform. The controllermay serve a browser-based user interface (UI)that is the primary interface for monitoring, analyzing, and troubleshooting the monitored environment. Specifically, the controllercan receive data from agents(and/or other coordinator devices), associate portions of data (e.g., topology, business transaction end-to-end paths and/or metrics, etc.), communicate with agents to configure collection of the data (e.g., the instrumentation/tests to execute), and provide performance data and reporting through the interface. The interfacemay be viewed as a web-based interface viewable by a client device. In some implementations, a client devicecan directly communicate with controllerto view an interface for monitoring data. The controllercan include a visualization systemfor displaying the reports and dashboards related to the disclosed technology. In some implementations, the visualization systemcan be implemented in a separate machine (e.g., a server) different from the one hosting the controller.

Notably, in an illustrative Software as a Service (SaaS) implementation, a controllerinstance may be hosted remotely by a provider of the observability intelligence platform. In an illustrative on-premises (On-Prem) implementation, a controllerinstance may be installed locally and self-administered.

The controllersreceive data from different agents(e.g., Agents 1-4) deployed to monitor networks, applications, databases and database servers, servers, and end user clients for the monitored environment. Any of the agentscan be implemented as different types of agents with specific monitoring duties. For example, application agents may be installed on each server that hosts applications to be monitored. Instrumenting an agent adds an application agent into the runtime process of the application.

Database agents, for example, may be software (e.g., a Java program) installed on a machine that has network access to the monitored databases and the controller. Standalone machine agents, on the other hand, may be standalone programs (e.g., standalone Java programs) that collect hardware-related performance statistics from the servers (or other suitable devices) in the monitored environment. The standalone machine agents can be deployed on machines that host application servers, database servers, messaging servers, Web servers, etc. Furthermore, end user monitoring (EUM) may be performed using browser agents and mobile agents to provide performance information from the point of view of the client, such as a web browser or a mobile native application. Through EUM, web use, mobile use, or combinations thereof (e.g., by real users or synthetic agents) can be monitored based on the monitoring needs.

Note that monitoring through browser agents and mobile agents are generally unlike monitoring through application agents, database agents, and standalone machine agents that are on the server. In particular, browser agents may generally be embodied as small files using web-based technologies, such as JavaScript agents injected into each instrumented web page (e.g., as close to the top as possible) as the web page is served, and are configured to collect data. Once the web page has completed loading, the collected data may be bundled into a beacon and sent to an EUM process/cloud for processing and made ready for retrieval by the controller. Browser real user monitoring (Browser RUM) provides insights into the performance of a web application from the point of view of a real or synthetic end user. For example, Browser RUM can determine how specific Ajax or iframe calls are slowing down page load time and how server performance impact end user experience in aggregate or in individual cases. A mobile agent, on the other hand, may be a small piece of highly performant code that gets added to the source of the mobile application. Mobile RUM provides information on the native mobile application (e.g., iOS or Android applications) as the end users actually use the mobile application. Mobile RUM provides visibility into the functioning of the mobile application itself and the mobile application's interaction with the network used and any server-side applications with which the mobile application communicates.

Note further that in certain embodiments, in the application intelligence model, a business transaction represents a particular service provided by the monitored environment. For example, in an e-commerce application, particular real-world services can include a user logging in, searching for items, or adding items to the cart. In a content portal, particular real-world services can include user requests for content such as sports, business, or entertainment news. In a stock trading application, particular real-world services can include operations such as receiving a stock quote, buying, or selling stocks.

A business transaction, in particular, is a representation of the particular service provided by the monitored environment that provides a view on performance data in the context of the various tiers that participate in processing a particular request. That is, a business transaction, which may be identified by a unique business transaction identification (ID), represents the end-to-end processing path used to fulfill a service request in the monitored environment (e.g., adding items to a shopping cart, storing information in a database, purchasing an item online, etc.). Thus, a business transaction is a type of user-initiated action in the monitored environment defined by an entry point and a processing path across application servers, databases, and potentially many other infrastructure components. Each instance of a business transaction is an execution of that transaction in response to a particular user request (e.g., a socket call, illustratively associated with the TCP layer). A business transaction can be created by detecting incoming requests at an entry point and tracking the activity associated with request at the originating tier and across distributed components in the application environment (e.g., associating the business transaction with a 4-tuple of a source IP address, source port, destination IP address, and destination port). A flow map can be generated for a business transaction that shows the touch points for the business transaction in the application environment. In one embodiment, a specific tag may be added to packets by application specific agents for identifying business transactions (e.g., a custom header field attached to a hypertext transfer protocol (HTTP) payload by an application agent, or by a network agent when an application makes a remote socket call), such that packets can be examined by network agents to identify the business transaction identifier (ID) (e.g., a Globally Unique Identifier (GUID) or Universally Unique Identifier (UUID)). Performance monitoring can be oriented by business transaction to focus on the performance of the services in the application environment from the perspective of end users. Performance monitoring based on business transactions can provide information on whether a service is available (e.g., users can log in, check out, or view their data), response times for users, and the cause of problems when the problems occur.

In accordance with certain embodiments, the observability intelligence platform may use both self-learned baselines and configurable thresholds to help identify network and/or application issues. A complex distributed application, for example, has a large number of performance metrics and each metric is important in one or more contexts. In such environments, it is difficult to determine the values or ranges that are normal for a particular metric; set meaningful thresholds on which to base and receive relevant alerts; and determine what is a “normal” metric when the application or infrastructure undergoes change. For these reasons, the disclosed observability intelligence platform can perform anomaly detection based on dynamic baselines or thresholds, such as through various machine learning techniques, as may be appreciated by those skilled in the art. For example, the illustrative observability intelligence platform herein may automatically calculate dynamic baselines for the monitored metrics, defining what is “normal” for each metric based on actual usage. The observability intelligence platform may then use these baselines to identify subsequent metrics whose values fall out of this normal range.

In general, data/metrics collected relate to the topology and/or overall performance of the network and/or application (or business transaction) or associated infrastructure, such as, e.g., load, average response time, error rate, percentage CPU busy, percentage of memory used, etc. The controller UI can thus be used to view all of the data/metrics that the agents report to the controller, as topologies, heatmaps, graphs, lists, and so on. Illustratively, data/metrics can be accessed programmatically using a Representational State Transfer (REST) API (e.g., that returns either the JavaScript Object Notation (JSON) or the extensible Markup Language (XML) format). Also, the REST API can be used to query and manipulate the overall observability environment.

Those skilled in the art will appreciate that other configurations of observability intelligence may be used in accordance with certain aspects of the techniques herein, and that other types of agents, instrumentations, tests, controllers, and so on may be used to collect data and/or metrics of the network(s) and/or application(s) herein. Also, while the description illustrates certain configurations, communication links, network devices, and so on, it is expressly contemplated that various processes may be embodied across multiple devices, on different devices, utilizing additional devices, and so on, and the views shown herein are merely simplified examples that are not meant to be limiting to the scope of the present disclosure.

illustrates a deploymentof a limited multicast route tracing mechanism. For example, limited multicast route tracing mechanism may include an Internet Engineering Task Force (IETF) Mtrace version 2 (Mtrace2) IP multicast traceroute facility (RFC 8487). Limited route tracing mechanism may be used to trace an IP multicast routing path within a multicast tree.

For example, a multicast treemay include a plurality of nodes(e.g., nodes-. . .-N). The nodesmay be network connection points such as electronic devices attached to a network that are configured for creating, receiving, and/or transmitting information over a communication channel. For example, each of the nodesmay be a switch, a router, a computer, a server, etc.

Each of the nodesmay be uniquely identifiable within the network so that information may be properly routed to a correct device. For example, each of the nodesmay be identifiable by a unique network address (e.g., IP address). Each of the nodesmay additionally, or alternatively, belong to, subscribe to, and/or be identifiable by a multicast group address.

In multicast tree, each of the nodesmay be interconnected by one or more communication channelsforming a communications web or network. Data may be communicated between given nodesacross branches of the multicast treethat are uniquely identifiable by the sequence of particular nodesand/or particular communication channelsacross which it is propagated.

For instance, multicast treemay include a source of multicast traffic, such as multicast source. The multicast sourcemay be located at the root of multicast tree. The multicast sourcemay send a multicast traffic flowto one or more receivers(e.g., receiver-. . .-N). The one ore more receiversmay include data receiving devices and/or data communication endpoints located at the end of a respective branch of the multicast tree.

Each multicast data flowmay be identifiable by a state entry for the source tree. The state entry may be based on the notation (S, G) where S represents the IP address of the multicast source(e.g., 10.1.1.1) and G represents the group address (e.g., multicast address) for a group of hosts in a computer network that are available to process datagrams or frames (e.g., 232.1.1.1).

The data flowmay be communicated from the multicast sourceto a first node (e.g., node-). The first node may be a node having a head-node role in the multicast tree. For example, the first node may operate as a first-hop router which is directly connected to the multicast sourceand/or which may be a router on which a traffic engineering (TE) tunnel is configured.

The first node may replicate the multicast packets of the multicast data flowfrom its incoming interface and send copies of them on its outgoing interfaces. In this instance, the first node may send a copy to a second node (e.g., node-).

The second node may replicate the multicast packets of the multicast data flowfrom its incoming interface and send copies of them on the outgoing interfaces. In this instance, the second node may be a branching point where the multicast treebranches into two separate branches. For instance, the second node may create a first branch where it forwards a copy of the multicast packets of the multicast flowto a third node (e.g., node-) and a second branch where it forwards a copy of the multicast packets of the multicast data flowto a fifth node (e.g., node-).

The multicast data flowmay be propagated node-by-node/hop-by-hop down the first branch to the fourth node (e.g., node-), and then to the fifth node (e.g., node-). The fifth node may be a node having a tail-node role in the multicast tree. For example, the fifth node may operate as a last-hop router, may be directly connected to a receiver (e.g., receiver-) and/or may be a router on which a branch of the TE tunnel terminates.

In addition, the multicast flowmay be propagated down the second branch to the sixth node (e.g., node-) and then to a seventh node (e.g., node-). The seventh node may also be a node having a tail-node role in the multicast tree. For example, the seventh node may operate as a last-hop router, may be directly connected to a receiver (e.g., receiver-) and/or may be a router on which a branch of the TE tunnel terminates.